Water cooled stoker



W. V. SAUTER EIAL Dec. 1, 1942.

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' "WATER COOLED STOKER I Filed Nov. 23, 1938 3 Sheets$heet 2 1, 1 w. v. SAUTER ETAL 2,303,866

WATER COOLED STOKER Fi1ed.Nov. 23, 19:58 3 sheets-sheet 3 Ma a/21 JZL zer 4/,

Patented Dec. 1 1942 WATER COOLED STOKER William V. Sauter, Philadelphia,

Bennett, Merion,

and Joseph S.

Pa., assignors to American Engineering Company, Philadelphia, Pa., a corporation of Pennsylvania Application November 23, 1938, Serial No. 241,898

13 Claims.

This invention relates to stoker furnaces, and more particularly to stokers of the fluid cooled type.

One object of the present invention is to provide a simplified and generally. improved stoker of the fluid cooled type which insures continuity of service under all conditions of operation.

" Another object is to provide in a stoker of the stated character improved tuyre constructions having extended surfaces disposed in intimate contact with fluid conducting tubes and the incoming draft air, whereby they are maintained relatively cool during operating periods of the furnace.

A further object is to provide tuyre members of resilient construction to enable the ready assembly thereof on the tubes of the fluid cooled section of the stoker, and to insure proper contact between said members and the tubes.

Other and further objects will become apparent as'the description of the invention progresses.

Of the drawings:

Fig. 1 is a longitudinal sectional View taken through one of the retorts of an inclined grate underfeed stoker.

Fig. 2 is a transverse sectional view taken through one of the tuyre chambers of the stoker shown in Fig. 1, showing the construction of the tuyre members forming the preferred embodiment of the present invention.

Fig. 3 is an enlarged fragmentary side view, showing the construction of the side tuyere members of the tuyere unit shown in Fig. 2.

Fig. 4 is a longitudinal sectional view taken through one of the tuyere chambers of the stoker-shown in Fig. 1.

Fig.5 is a view taken substantially along line 5-5 of Fig. 4.

Fig. 6 is a sectional View taken substantially along line 6--6 of Fig. 4.

Fig. 7 is a transverse sectional view illustrating another embodiment of the present invention. Fig. 8 is a sectional view taken substantially along line 8-8 of Fig. 7.

Fig. 9 is a perspective view of one of the intermediate tuyre members shown in Figs. 7 and 8.

Fig. 10 is a transverse sectional view of a further embodiment of the present. invention. Fig. 11 is a view partly in section, taken along line IIII of Fig. 10, and

Fig. 12 is a perspective View of one of the tuyre members shown in Figs, 10 and 11.

Referring to the drawings, the numeral I designates generally a stoker of the inclined grate, underfeed type, having alternately disposed retorts 2 and tuyere rows 3. The bottom of each retort has provided therein a series of alternately disposed pushers 4 and dead plates 5. Fuel is supplied to the stoker from hoppers 6 disposed exteriorly of the front wall I of the furnace. The fuel gravitating in hoppers 6 enters cylinders 8 from which it is fed to the retorts2 by means of rams 9 operated by any suitable power mechanism It. The fuel is underfed along the stoker by the pushers 4, the consumed fuel being fed into an ash pocket A disposed at the end of the stoker. The pushers 4 are also actuated by the power mechanism I0 through the link and lever mechanism indicated generally at I I.

Each retort 2 is defined at the sides thereof by inclined, longitudinally extending side plates I2 and I3, which also define the sides of the tuyre chambers I 4 disposed between adjacent retorts 2. Side plates I 2 and I3 have supported thereon series of tuyre supports I5 and I6 respectively. Tuyere supports I5 and I6 are secured to the inwardly extending flanges I1 and I8 respectively, of side plates I2 and I3 by any suitable means, such as by bolts I9. Extending lon-' gitudinally over the upper end of each tuyre chamber I 4 are a pair of substantially parallel tubes 26 and 2|. the upper end of stoker I, as shown at 22, so that the upper ends thereof lie in abutting relation with the inner surface of wall I. The upper ends of tubes 2I and 22 may terminate in one of the steam drums of a boiler (not shown) or in a header'which in turn may be connected to the boiler, as desired. The lower ends of tubes 20 and El are bent downwardly and forwardly, as shown at 23, and terminate in a header 24 disposed near the bottom of ash pocket A. The lowermost dead plate 25 of each retort- 2 has mounted in cooling relation therewith one or more fluid conducting tubes 21. These tubes extend rearward- I 1y from a header 28 mounted in any suitable manner beneath the stoker. The rearwardly dis posed ends of tubes 21 are also bent and forwardly in substantially parallel relation with the tubes 20 and 2I, and also terminate at the lower ends thereof in header 24. Headers and 28 may also be connected to the boiler by downtake and riser connections 29 and 30 respec-, tively. Tuyere supports l5 and I6, as shown more particularly in Fig, 2, are provided with rounded upper surfaces 3I and 32 respectively. Extending and tubes 20 and 2I are side tuyre members33 and 34. Each of the tuyr members 33 and 34" is similar in construction" and accordingly a" de-' Tubes 20 and 2| are bent near downwardly between rounded surfaces 3| and 32' Fig. 2.

tailed description of one will sufiice for both. For the purpose of illustration, one of the tuyere members 33 will now be described in detail.

' Each tuyere member 33 is comprised of spring steel construction and is provided with a substantially arcuate outer surface 35 and a pair of substantially arcuate inwardly extending legs 36 and 31. Outer'surface 35 has extending lengthwise thereof a series of punched out tongues 38 which provide a series of openings through which draft air may pass to the fuel bed. As shown particularly in Figs. 1 and 3, the tongues 38 partially cover the openings, and thereby prevent siftings from passing into the tuyere chamber.

As pointed out before, tuyre members 33 and 34 are composed of spring steel, and the legs 36 and 3'! thereof are so bent as to have a curvature corresponding with the upper surface of the tuyere supports and with the tubes and 2!.

To assemble a tuyere member 33 or 34 in'position, the legs thereof are inserted in the space between the tuyere supports and the tubes, and the member is then 'urged into position which,

when assembled, corresponds to that shown in The outer surfaces of the legs and 31, it will now be observed, lie in intimate contact with the curved surface 3! and the tube respectively. To prevent'movement out of position the tuyere members 33 and 34 may be spotwelded to the tubes 20 and 2!.

Also extending between and lying in intimate contact with tubes 23 and 2! are a series of longitudinally extending intermediate tuyre members 39. Tuyere members 39 are somewhat on the order of tuyere members 33 and 34 and are also of spring steel construction. Tuyre members 39 are provided with a relatively flat upper surface 49 and a pair of downwardly extending legs 4! and 42. The upper surface 4! is provided with a hinged series of stamped out tongues 43 which provide a series of openings for draft air. The tongues 43, like the tongues 38 provided on tuyere members 33 and 34, partially cover the air openings, as shown more particularly in Fig/Land consequently the passage of siftings through said openings is reduced to a minimum. To assemble a tuyere member in position the legs 4! and 42 are forced between the tubes 20 and 2! so as to assume the position shown in Fig. 2. When in this position the outer sides of the legs 4! and 42 lie in intimate contact with the inner surfaces of said tubes. It will be noted that the upper surface of tuyere members 39 are disposed above the center line of the tubes 20 and 2!, and consequently the weight of the fuel supported thereby will not move them out of operative position. To prevent the legs 4-! and 42 from moving out of intimate relation with the tubes 20 and 2! due to expansion and contraction, the legs 4! and 42 may be welded to the said tubes. To prevent distortion of the tubes under load a series of tie members 44 are provided. These tie members are secured to the bolts 45 depending from and integral with said tubes 20 and 2!. As shown in Fig. 2, the stud bolts 45 extend through apertures provided in tie member 44, and nuts 46 secure the parts in position. Tuyre supports l5 and I5 have also extending inwardly thereof aperturecl ears 4! and 48 respectively. These ears are secured to the depending portion 49 of tie members 44 in any suitable manner such as by bolts 50.

The side tuyere members 5! and 52 provided at the front or upper end of the stoker are of somewhat different construction from the side tuyere members 33 and 34 disposed therebeneath. These members are provided with inwardly extending flanges 53 and 54 which seat upon inwardly extending flanges provided at the upper edges of side plates !2 and I3 respectively, and bolts 55 (Fig. 4) extending through said flanges secure the said tuyere members in position. The portions 55 and 51 of tuyre members 5| and 52 are slightly curved at the upper ends thereof, as shown at 58 (Fig. 1), and lie in abutting relation with tube 20 and 2!. The upper edges 59 of tuyre members 5! and 52 are flat and are provided with inwardly extending flanges 60 and 6!, as shown more particularly in Fig. 6. A cover plate 62 having open tube receiving recesses 63 and 64, at the rearwardly disposed end thereof seats upon flanges 63 and 5!, and stud bolts 65 extending through said plate, and tapped apertures in said flanges rigidly secure said cover plate in position. As shown in Figs. 1, 4 and 5, cover plate 32 extends across the top of the upper end of the tuyere chamber and around tubes 20 and 2!, thereby preventing the passage of fuel siftings into the tuyere chambers. The upper intermediate tuyre membed 66 is similar in construction to the intermediate tuyere members 39 except that the legs 6'! thereof, which engage the inner surfaces of tubes 20 and 2!, are shorter than the legs of tuyere members 33. The upper surface 38 of tuyere member 58 is curved, as shown in Fig. 4, to conform with the curvature of tubes 20 and 2!, and is secured to the downwardly inclined tongue 68 of plate 52 by a stud bolt 10. The rearwardly disposed ends of the projections l! and 72 of plate 62 abut the upper end of side tuyere meubers 5! and 52, as shown more particularly in Fig 5.

By this construction it is seen that an effective seal is provided to prevent siftings from passing into the tuyre chamber, The lowermost side tuyere members 33 and 34, as well as the lowermost intermediate tuyre member 39, are so formed that the lower ends thereof will lie flush with lower dead plate 25 and the tuyre plate 13, as shown in Figs. 1 and 4. Draft air is supplied to the various tuyere members by means of a plenum chamber i4, which in turn may be supplied with air by any suitable fan or blower mechanism (not shown) through a communicating passage 15.

Figs. '7, 8 and 9 illustrate a modified tuyere construction consisting of a pair of tubes 16 and 11, having fins l8 and I9, welded or otherwise secured respectively to the outer sides thereof, and a series of intermediate tuyere members disposed in intimate contact with the inner surfaces of said tubes. In this construction the side plates 8! and 82 defining the side walls of the tuyere chamber 83, have bolted, or otherwise secured thereto, series of tuyere supports 84 and 85 respectively. The upper ends of tuyere supports 84 and 85 have provided thereon a series of spaced projections 86 and 81, respectively, upon which the fins 18 and 79 rest. By this construction series of lateral air passages are provided between the fins 18 and i9. and the upper ends of tuyere supports 84 and 85.

Each intermediate tuyre member 83 is comprised of an upper, relatively fiat portion 88, and a pair of curved legs 89 and 9B. The rearwardly disposed end 88' of surface 88 extends beyond the legs 89 and 93, and in assembly overlaps the next lower tuyre member Bil of the series, and forms therewith, and the tubes at the sides thereof, passages 9! for draft air. To assemble 2,303,866 the intermediate tuyere members 80 in position the legs 89 and 90 thereof are forced between the tubes so as to occupy the position shown in Fig. 8. The legs may then be welded to the tubes so as to retain the said tuyre members in position.

Tubes 16 and I? have also provided thereon depending stud bolts 92 and 93, the reduced lower ends of which extend through apertures provided in tie bars 9 3, and nuts 95 secure the parts in position. The outer ends of tie bars 94 extend into longitudinally extending recesses 96,

96 provided in tuyere supports 84 and 85. By this construction the tubes '16 and I7, and the tuyere members associated therewith, are effectively supported in position, the longitudinal recesses 96 permitting longitudinal expansion and contraction of the parts due to the variable temperatu're conditions to which the parts are exposed.

Figs. 10, 11 and 12 illustrate a further embodiment of the present invention. In this construcs tion the upper end of each tuyere chamber 8'! is bridged by longitudinally extending tubes 98 and 99 to which are respectively secured tuyere members I and NH. The sides of tuyre chamber '91 are defined by side plates I92 and I03, to the upper edges of which are bolted tuyere supports I84 and I respectively. Tuyre member IE0 is provided with a substantially semi-circular re- "cess I135 which receives the under surface of tube 98 and is secured thereto in any suitable manner, such as by spot-welding, as indicated at IN. The upper inner end of each tuyre member Iilii is provided with a short, longitudinally extending flange I08 which is spaced slightly from a similar flange I69 extending inwardly from tuyre member II. The outer side of tuyere member I0!) is provided with a laterally extending portion I II] which terminates in a downwardly extending portion III, which in turn abuts the outer sides of projections II2 extending outwardly from the upper end of tuyere supports I64.

Each tuyre member IIlI is also provided with a semi-circular recess H3 which engages the under side of tube 9%. Tuyere member IOI has also provided at the outer side thereof, a laterally extending portion I I4 which terminates in a downwardly extending portion II5, which engages the outer sides of projections Ilii, extending laterally from the upper end of tuyere supports I05. It therefore is seen that the space between flanges I08 and I09 provide the necessary opening between the tubes through which draft air may enter into the furnace. The downwardly extending portions III and H5 also form withthe upper ends of tuyre supports HM and IE5 downwardly extending passages through which draft air may also enter the furnace. Each tuyere member IiiI is also secured to tube 99, by spot-welding, as indicated at II'i. Tuyere members I00 and Iill have also provided at the .bottom of the semi-circular surfaces thereof a recess IIB through which a stud bolt H9, depending from the tubes, may. extend. These bolts also extend through apertures provided in tie bars I20, similar in construction to the tie bars 94 shown in Figs. 4 and '7, and which in turn are supported in suitable recesses provided in tuyere supports I04 and I05.

In all of the constructions just described, it willbe observed that a relatively large area of the tuyere members are disposed in intimate con tact with the fluid conducting tubes. The heat absorbed by the tuyere members therefore is readily conducted to the fluid circulating through said tubes, and as a result said tuyere members are maintained relatively cool under all condition of operation. It will also be observed that the tuyere members are so constructed that a relatively large area is exposed to the incoming draft air, and consequently the cooling effect thereofis also imparted to the tuyere members,

As pointed out before, the tuyere members are constructed of resilient material, and when forced between the tubes snap into position and make intimate contact therewith.

It therefore is apparent that the various constructions comprising the present invention are not only simple in manufacture, and easy to install, but are capable of performance at maximum efiiciency under the most severe conditions of furnace operation. By maintaining the various tuyere elements relatively cool, burnouts are reduced to a minimum, and consequently stokers may be operated without interruption for long periods of time.

While the embodiments herein shown and described are admirably adapted to fulfill the objects primarily stated, it is to be understood that the invention is not to be limited thereto, since it may be embodied in other forms, all coming within the scope of the claims which follow.

What is claimed is: e

1. A tuyere construction for stoker furnaces comprising spaced, longitudinally extending members defining the side walls of a tuyere chamber, one or more fluid conducting tubes extending longitudinally over the top of said chamber, and tuyre members disposed between said'tubes and said side members, said tuyere members being formed of relatively thin material, and a substantial portion of each of said tuyre members being of arcuate construction and conforming substantially to the curvature of said tubes,

whereby in assembly said arcuate portions of said tuyere members lie in intimate contact with said tubes, and means for preventing lateral distorcuring said tie bar in position.

2. A tuyere construction for stoker furnaces comprising two or more longitudinally disposed fluid conducting tubes, spaced supporting means for said tubes, tuyere members disposedbetween each of said supporting means and said tubes, a substantial portion of each of said tuyere members lying in intimate thermal contact with said tubes whereby said tuyere members are maintained relatively cool during operating periods of the furnace, additional tuyere members disposed between said tubes, substantial portions thereof lying in intimate contact with said tubes, and means for preventing lateral distortion" of said tubes, said last mentioned means comprising a tie bar, and bolt means secured to and depending from each of said tubes for securing said tie bar in position.

3. A tuyre member adapted for assembly between. a pair of fluid conducting tubes, said .tuyere member being constructed of sheet metal -material and being formed with a pair of down- @tioned means comprising a tie bar, and bolt means secured to and depending from each of said tubes for securing said tie bar in position.

"4."A' tuyere construction'for stoker furnaces extending longitudinally over the top of said chamber, and tuyre members disposed between said tubes and said side members, each of said tuyere members being formed of resilient sheet metal and having a pair of legs of arcuate construction, and a fuel abutting portion bridging said legs, said tuyere members being so constructed that upon assembly thereof in position the arcuate portions of said legs lie in intimate contact with said tubes and supporting members.

5. A tuyere construction for stoker furnaces comprising spaced, longitudinally extending members defining the side walls of a tuyere chamber, one or more fluid conducting tubes extending longitudinally over the top of said chamber, and tuyere members disposed between said tubes and said side members, each of said tuyre members being formed of resili nt sheet metal and having a pair of legs of arcuate construction, a fuel abutting portion bridging said legs, said tuyere members being so constructed that upon assembly thereof in position the arcuate portions of said legs lie in intimate contact with saidtubes and supporting members, and additional tuyere members disposed between said tubes, each of said additional tuyere members also comprising a fuel supporting portion, and a pair of depending legs of arcuate construction 'which, in assembly, intimately engage the inner sides of said tubes.

6. A tuyere construction for stoker furnaces comprising spaced, longitudinally extending members defining the side walls of a tuyere chamber, one or more fluid conducting tubes extending longitudinally over the top or said chamber, and tuyere members disposed between said tubes and said side members, each of said tuyere members being formed of resilient sheet metal and having a pair of legs of arcuate construction, a fuel abutting portion bridging said legs, said tuyere members being so constructed that upon assembly thereof in position the arcuate portions of said legs lie in intimate contact with said tubes and supporting members, additional tuyere members disposed between said tubes, each of said additional tuyere members also comprising a fuel supporting portion, and a pair of depending legs of arcuate construction which, in assembly, intimately engage the inner side of said tubes, and each of said tuyere members having a series of openings therein for draft air,

and tongues partially overlying said openings.

'7. An inclined underfeed stoker, comprising alternately disposed retorts and tuyeres, spaced side plates defining the side walls of said retorts and tuyere chambers, a pair of longitudinally extending tubes disposed above each of said chambers, a series of supporting members mounted on each of said side plates for supporting said tubes, a plurality of side tuyere members disposed between said tubes and said supporting members, a plurality of intermediate tuyere members disposed between said tubes, each of said tubes being curved upwardly at the upper end thereof, a pair of side tuyere members provided at the upper end of said stoker, a portion of each of said side members being curved partially in conformity with the curvature of said tubes and having an upper, substantially horizontally disposed edge, a cover plate supported -upon said horizontally disposed edges, an extension provided on the upper of said intermediate tuyere members, said extension being curved in conformity with the curvature of said tubes, and means for securing the upper end of said extension to said cover plate.

8. An inclined underfeed stoker, comprising alternately disposed retorts and tuyeres, spaced side plates defining the side walls of said retorts and tuyere chambers, a pair of longitudinally extending tubes disposed above each of said chambers, a series of supporting members mounted on each of said side plates for supporting said tubes, a plurality of side tuyere members disposed between said tubes and said supporting members, a plurality of intermediate tuyere members disposed between said tubes, each of said tubes being curved upwardly at the upper end thereof, a pair of side tuyre members provided at the upper end of said stoker, a portion of each of said side members being curved partially in conformity with the curvature of said tubes and having an upper, substantially horizontally disposed edge, a cover plate supported upon said horizontally disposed edges, an extension provided on the upper of said intermediate tuyere members, said extension being curved in conformity with the curvature of said tubes, means for securing the upper end of said extension to said cover plate, and each of said tuyere members comprising a fuel abutting portion, and a pair of substantially arcuate legs, adapted in assembly to lie in intimate contact with said tubes.

9. An inclined underfeed stoker, comprising alternately disposed retorts and tuyeres, spaced side plates defining the side walls of said retorts and tuyere chambers, a air of longitudinally extending tubes disposed above each of said chambers, a series of supporting members mounted on each of said side plates for supporting said tubes, a plurality of side tuyere members disposed between said tubes and said supporting members, a plurality of intermediate tuyre members disposed between said tubes, each of said tubes being curved upwardly at the upper end thereof, a pair of side tuyre members provided at the upper end of said stoker, a portion of each of said side members being curved partially in conformity with the curvature of said tubes and having an upper, substantially horizontally disposed edge, a cover plate supported upon said horizontally disposed edges, an extension provided on the upper of said intermediate tuyre members, said extension'being curved in conformity with the curvature of said tubes, means for securing the upper end of said extension to said cover plate, and each of said tuyere members being constructed of resilient sheet metal material andhaving a fuel abutting surface, and a pair of substantially arcuate legs adapted in assembly to snap into engagement with said tubes.

10. An inclined underfeed stoker, comprising alternately disposed retorts and tuyres, spaced side plates defining the side walls of said retorts and tuyere chambers, a pair of longitudinally extending tubes disposed above each of said chambers, a series of supporting members mounted on each of said side plates for supporting said tubes, a plurality of side tuyere members disposed between said tubes and said supporting members, a plurality of intermediate tuyre members disposed between said tubes, each of said tubes being curved upwardly at the upper end thereof, a pair of side tuyre members provided at the upper end of said stoker, a portion of each of said side members being curved partially in conformity with the curvature of said tubes and having an upper, substantially horizontally disposed edge, a cover plate supported upon said horizontally disposed edges, an extension provided on the upper of said intermediate tuyere members, said extension being curved in conformity with the curvature of said tubes, means for securing the upper end of said extension to said cover plate, each of said tuyere members being constructed of resilient sheet metal material and having a fuel abutting surface, and a pair of substantially arcuate legs adapted in assembly to snap into engagement with said tubes, and the said fuel abutting surfaces of each of said tuyre members having a series of openings therein for draft air, and means partially overlying said openings to prevent the passage of siftings into said tuyre chambers.

11. A stoker comprising alternately disposed retorts and tuyres, spaced side plates defining the side walls of said retorts and tuyre chambers, a pair of longitudinally extending tubes disposed above each of said chambers, a series of supporting members mounted on each of said side plates for supporting said tubes, spaced, upwardly extending projections provided on each of said supporting members, laterally extending fins provided at the outer sides of each of said tubes, said fins engaging said upwardly extending projections and defining therewith series of passages for draft air, and a series of tuyere members provided between said tubes, each of said tuyere members comprising an upper fuel supporting surface and a pair of downwardly, substantially arcuate legs adapted in assembly to lie in intimate contact with the inner surfaces of said tubes.

12. A tuyre construction for stoker furnaces comprising a pair of longitudinally disposed fluid conducting tubes, spaced side walls forming a tuyre chamber, means mounted in intimate contact with said tubes and forming between said tubes openings for draft air, means extending outwardly from said tubes and disposed in operative relation with the upper ends of said side walls forming additional openings through which draft air may pass, and means for preventing lateral distortion of said tubes, said last mentioned means comprising a tie bar, and bolts secured to and depending from said tubes for securing said tie bar in position.

13. A tuyere construction for stoker furnaces comprising a pair of longitudinally disposed fluid conducting tubes, spaced side walls forminga tuyre chamber, means constructed of relatively thin material, mounted in intimate contact with 

